LONG TERM MEMORY

1
LONG TERM MEMORY

• AIMS OBJECTIVES
• The aim of this lecture is to review current
  approaches to long term memory.
• At the end of the lecture you will have learned
• What is meant by episodic and semantic memory
• How we learn information store it in long term
  memory
• What is meant by explicit and implicit memory
  processing
• Why data from amnesia is important

• CORE READING
• Parkin, A. (2000). Essential Cognitive
  Psychology. Psychology Press, Chap 5.
• SUPPLEMENTARY READING
• Baddeley, A. (1997). Human Memory Theory
  Practice. Psychology Press (LEA).
• Logie, R. (1999). Working memory. The
  Psychologist, 12, 174-178.

2
Long term memory

• Long term memory (LTM) refers to our permanent
  store of knowledge.
• Encodinglearning new information.
• Capacity of long term memory is unknown.

• Atkinson and Shiffrin (1971) assumed LTM was a
  single store.
• Are there different memory systems in LTM or
  different types of information?

3
Two types of encoding

• Procedural memory.
• knowing how.
• procedural knowledge is automatic, unconscious or
  non-conscious and is reflected in our actions.
• e.g., driving a car.

• Declarative memory.
• knowing that.
• declarative knowledge is effortful, open to
  conscious inspection and requires symbols.
• e.g., simple addition.

4
Procedural memory

• Motor skills
• playing the guitar.
• becomes automatic.
• Grammar acquisition
• using plurals and past tense in language.
• Taught to use ed
• becomes automatic

• Perceptual learning
• what is leaned cannot be described e.g.,
  melodies.
• Classical conditioning
• fear of lifts is not open to conscious
  inspection.
• anxiety (US) lifts (CS)
• -gt lift phobia (CFR).

5
Procedural skills

• Many reports of patients with amnesia who retain
  prodedural skills, e.g. drawing.
• Patient is unaware that s/he possesses skills.

• Dunn (1845) -dressmaker
• Dana (1894) - piano player
• Liepmann (1910) - chess player

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Episodic and semantic memory

• Episodic memory is memory for specific episodes
  in our lives
• Occurring at particular places/times e.g., what
  you had for lunch.
• Endel Tulving (1972).

• Semantic memory is like a mental thesaurus
• It contains knowledge about words symbols,
  general knowledge about the world and our memory
  for other facts.
• Are these two types of memory dissociable?

7
Long term memory effects

• Renaissance bump
• Memory for events that occurred in a persons
  adolescence are better than for events that
  occurred in middle age for the normal elderly.
• no effect on semantic.

• Temporal gradient
• Dementia is a progressive memory impairment found
  in patients with Alzheimers disease.
• Memory for recently acquired information declines
  first but memory for early acquired events is
  often better preserved.
• no effect on semantic.

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Renaissance bump
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45 50 55 60
65 70 Age of patient when event
occurred
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Registration impaired
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Semantic memory preserved

• Some amnesics have poor episodic memory for day
  to day events but may retain a lot of
  factual/semantic knowledge about the world
  e.g.,what is the capital of France?

• Gabrieli, Cohen and Corkin (1983).
• HM was unable to learn meanings of new words i.e.
  unable to acquire new semantic memories as well
  as episodic memories.

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Semantic dementia

• Intact episodic memory with impaired semantic
  memory (words, objects).
• This is called semantic dementia.
• Patients gradually losing tissue in the
  neo-cortex.

• Hodges et al (1995)
• Patient JL showed a decline in semantic memory
  but preserved episodic memory for day to day
  events.
• Alzheimers patients the reverse pattern.

13
(Auto)biographical memories

• Temporal gradient to memory loss about self.
• Self memory system (SMS) Martin Conway.
• Working self
• Autobiographical knowledge about self.
• Confabulation imagined knowledge about the self
  (Conway et al 2003)

• Some patients cannot remember information about
  other people i.e. their faces, names etc.
• Other patients with brain damage cannot remember
  detailed information about themselves including
  specific personal events.
• Retrograde episodic amnesia

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Prefrontal cortex
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False recollection

• Bell Tree Gun Stranger
• Window Balloon Crayon Garden
• Hat Bird Church Glasses
• Barn Mountain Turkey Stocking
• Ranger Coffee Fountain Shoe
• Nose Mouse Boat Teacher
• Weather River Hot Stove
• School Towel Parent Nest
• Hand Curtain Water Children
• Pencil Flower Farmer Drum
• Home Colour Rose Toffee
• Fish Desk Cloud Lamb
• Moon House

16
Recognition tests

• Bell Tree Gun Stranger
• Window Balloon Crayon Garden
• Hat Bird Church Glasses
• Barn Mountain Turkey Stocking
• Ranger Coffee Fountain Shoe
• Nose Mouse Boat Teacher
• Weather River Hot Stove
• School Towel Parent Nest
• Hand Curtain Water Children
• Pencil Flower Farmer Drum
• Home Colour Rose Toffee
• Fish Desk Cloud Lamb
• Moon House

17
Flashbulb memories

• Brown and Kulik (1977).
• Asked participants how they heard the news of the
  death of John Kennedy (and other events).
• Memories accompanied by a vivid and detailed
  recollection of the event.
• Islands of memory.

• But, a vivid and detailed recollection is not
  necessarily an accurate one.
• Old memories are usually very well rehearsed and
  elaborated so we do not know whether these
  islands of memory are genuinely discrete units in
  memory.

18
Explicit and implicit memory

• Explicit memory
• is memory revealed when performance requires
  conscious recollection of prior experiences.

• Implicit memory
• is memory revealed when performance is
  facilitated in the absence of conscious
  recollection of the event itself.

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episodic
semantic
declarative
procedural
visual
verbal
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Summary

• Long term memories can be divided into episodic
  and semantic memories
• Access to long term memories can be seen on
  implicit and explicit tasks
• Dissociations between long term memory stores
  supported by the data from amnesia.